Stroke is the most prominent cause of permanent disability in industrialized countries. Motor disabilities are the most common deficits after stroke. Rehabilitation exercises are proven to be efficient to regain motor control, provided the training is intense, the patient is guided in the therapy and receives adequate feedback.
Recently, training devices for unsupervised home use have been introduced. These devices work without a therapist, which means that, once a patient has been introduced to the device, the patient may carry out rehabilitation exercises more frequently, which again increases and accelerates his recovery.
Technical solutions for unsupervised home stroke rehabilitation require the use of sensors for acquiring the patient's posture during exercises. These sensors can be either inertial sensors such as the popular MT9 sensor provided by XSENS, or camera-based Systems such as e.g. the Opti Track system manufactured by Natural Point, respectively.
In both devices, the patient's movements are recorded, compared to a template posture and/or movement and the difference is then reported to the patient in a suitable way. The Core:Tx system manufactured by Performance Health uses a rendered human-like figure for displaying the template posture and/or movement that the patient is supposed to perform. The patient wears an inertial sensor on the affected limb. His own movement is not displayed on screen. A green or red light indicates agreement or disagreement of template and patient movement. These devices are for example described in U.S. Pat. No. 6,834,436.
Displaying the difference between the provided template and the patient's movement is crucial for the effectiveness of a home rehabilitation system, as stroke victims are often not aware of their deficits and show genuine surprise that their performance does not reflect the movement templates.
The existing approaches to home rehabilitation, as for example described in U.S. Pat. No. 6,231,527, use feedback systems that the user finds difficult to get acquainted with. Existing systems use a rendered figure for displaying the patient's movement. It is difficult for the user to identify himself with such a rendered figure. However, as mentioned above, perceiving one's own movement as being not according to the template is a crucial step on the road to recovery for this patient group.
Furthermore, existing Systems use a Computer screen for displaying feedback. However, stroke victims are mostly elderly persons that are not acquainted with Computers. Therefore it is desirable to use a feedback device that provides advantages in terms of ease of use, intuitivity of use, and efficiency of use, especially for elderly people.